It's interesting that they give out stock vs. cash as an employee referral bonus. I've never seen companies do that before, I'm not sure why.
It's usually either a meaningless amount of cash ($250? Really? For a $100k/yr engineer? At that point just give a non-cash gift), or a substantial amounts of cash (approximately 25-50% of a contingency recruiter's fee).
Most companies I've been at/seen have at least $5k referral bonuses. At one company I knew of one employee who had gotten $25k in one year: definitely nothing to balk at.
It's usually either a meaningless amount of cash ($250? Really? For a $100k/yr engineer? At that point just give a non-cash gift), or a substantial amounts of cash (approximately 25-50% of a contingency recruiter's fee).